I have recently overclocked my palit gtx 780 in msi afterburner to plus 150 ( MHz?) core clocked and plus 150 (MHz?) memory clock and changed the fan settings in accordance. At first this ran fine on my gpu, a bit more noise and heat but the heat appeared to stay below 70 C . Score in fire strike benchmark went from 8576 to 9242 or thereabouts. Then I decided to restart and OC CPU, my i5 4670k. As I have a Z97 motherboard, I used the EZ mode overclock and overclocked it to the settings "gaming/ media, tower fan". I cannot remember the OC values it gave. However I remember it said there would be about a 20-30 percent increase in performance in 2 different values. I continued the boot, then the computer shut down. Then the computer restarted, and I went back into the bios and put the values back to the "gaming/media" one like an idiot. Then the computer shut down again and restarted, and I chose "boot normally" instead of startup repair. The login began, I was given a short BSoD, and now computer will start but no monitor display. Motherboard gives beep code for graphics card issue. What have I done and what should I do now? Fans still work on graphics card.